Effects of percolating water with graduated acidity upon the leaching of nutrients and the changes in some chemical properties of mineral soils

František Haman

doi:10.23986/afsci.71941

Abstract

Leaching of nutrients and the changes in some chemical properties of surface soil layer treated with solutions of gradual acidity were followed under laboratory conditions. The 25-cm-high columns of three soils, (A – fine sand, B - loam, C - clay loam), placed in plastic tubes were treated with deionized water (pH 6) and with three solutions (pH 5, pH 4, pH 3) of sulphuric acid. The washed out were determined in the leachates collected into plastic bags. The largest amount of nitrogen found in the leachates was in the form of nitrate and this was proportional to the content of organic matter in the soils. The leached amount of NH4-N was considerably lower and like potassium it was negatively dependent upon the clay content in the soils. The concentrations of K, Ca and Mg in the leachates rose in relation to the declining pH of percolating solutions. Especially in soil A, acid solutions of pH 5 (and lower) washed out very effectively the cations. Soils Band C (with a higher content of clay particles) showed a higher resistance to K, Ca and Mg leaching. The acidified water influenced even the pH of the surface layer (0—7,5 cm) of soils in the columns. The most marked decrease in pH values was found in soil A after an application of the solution with pH 3. A decrease in the content of basic cations (Ca and Mg) was parallel to the acidification of the upper layer of the soils.

Highlights

In the majority of industrialized European countries air pollution has been one of the most rapidly spreading phenomena in recent years
It should be mentioned that no fertilizers were used in this experiment. This means that the contamination of surface and ground water with nitrates may result from the application of nitrogen fertilizers and from an increased microbial activity of the soil provided that there are favourable conditions for the growth of microorganisms, i.e. a high content of organic matter, an optimum ratio between water and air in the soil, and an adequate temperature (Goh, 1972)
Both the potassium and the NH| ions were washed out from experimental soils in correlation with the content of clay particles and pH in soils. Korkman (1970) observed a negative correlation between the clay content in soil and the potassium and NH| movement from fertilizers applied

Summary

Introduction

In the majority of industrialized European countries air pollution has been one of the most rapidly spreading phenomena in recent years. Sulphur dioxide is very dangerous for all living organisms. It enters as a very dangerous compound of an acid character the soil with precipitations as well as the soil surface owing to a certain sorption capacity. In many European countries it has been noted that the acidity of rainfalls has increased considerably during the last twenty years. According to Od6n (1968), the acidity of rain water increased 100-fold in central Europe within the period between 1958 and 1965. There was a 200-fold increase in the acidity of precipitations in some parts of Scandinavia in comparison with 1956. In some localities of Western Europe and Scandinavia, the average annual values of the pH of rain water dropped as low as 4.0 in 1968, in the Netherlands this value was even lower

Methods

Results

Conclusion